Existing systems from the prior art, for example the modular multilevel converter M2C (U.S. Pat. No. 7,269,037; DE 101 03 031), the modular multilevel converter M2SPC (WO 2012 072197; DE 10 2010 052934; WO 2012 072168; WO 2012 072197; EP 2011 0179321; DE 2010 1052934; WO 2013 017186; DE 10 2011 108920) and various modifications (for example U.S. Ser. No. 13/990,463; U.S. Ser. No. 14/235,812; DE 10 2010 008978; DE 10 2009 057288; U.S. Pat. No. 3,581,212), can admittedly, in a manner similar to the present invention, dynamically combine single electrical energy stores with one another in order to allow energy delivery or energy acceptance with almost any current and voltage properties on the connections of the system. However, these known solutions require each electrical energy store to be implemented in a separate module. The electrical switches of the electrically interconnected modules allow, via suitable activation, dynamic alteration of the electrical interconnection of the electrical energy stores integrated in the respective modules, for example between electrical series interconnection of the electrical energy stores of different modules, electrically parallel interconnection of the electrical energy stores of different modules or a bypass of the electrical energy stores of at least one module, as a result of which the current is directed around the electrical energy store through suitable activation of the electrical switches that said electrical energy store is not incorporated in the circuit and hence is at least intermittently neither charged nor discharged. Correct operation, each module can contain only one electrical energy store, however. A combination of multiple electrical energy stores in one module cannot correct any inequalities in the individual electrical energy stores that arise as a result of aging processes or as a result of manufacturing tolerances, for example. Further, it is also not possible for different electrical energy stores, for example a battery and a capacitor, to be integrated into one module. The need to provide a separate module for each individual electrical energy store gives rise to high costs on account of the necessary additional electronic components, such as transistors and DC isolating, for example optical, transformers, for example, and requires complicated actuation on account of the high number of electrical switches to be controlled. Further, a high number of measuring detectors, for example for the module voltage and/or the module current, needs to be integrated into the system.